In motor vehicle washing equipment, the vehicle is moved relative to the washing assembly, wherein either the vehicle is pulled through the washing assembly by means of a conveyor belt or a portal assembly which carries the washing brush is moved with respect to the stationary vehicle. In such arrangements, the horizontal washing brush, whose axis is arranged transversely with respect to the direction of relative movement must be lifted from its lowest position, in which it washes the front of the vehicle at the level of the bumpers, up to the level of the roof, and then is lowered again when washing the rear of the vehicle. In order to raise and lower the washing brush, the apparatus has a control motor which acts by way of a transmission means and drive rollers on a conveyor cable, chain or the like which is connected to the carriages of the washing brush. A control means which is dependent on the deflection movement of the washing brush is provided for controlling the control motor.
Swiss Pat. No. 443 940 discloses apparatus of the above-indicated kind. In this known portal-type washing apparatus, the horizontal washing brush is mounted in a frame which is supported on respective sides in respective carriages which are pivotal about an axis extending transversely with respect to the direction of movement of the portal assembly. The frame has switching cam members which co-operate with a limit switch disposed on the carriage. As long as the horizontal washing brush is not in contact with the vehicle, the two pivot arms which form a part of the frame hand vertically downwardly. As soon as the vehicle bears against the brush, the frame is pivoted about its horizontal pivot axis and the cam members actuate the limit switch. The limit switch switches on the control motor and causes the washing brush to be lifted, together with the frame. Instead of the switching cam members, it is also possible to use a plurality of switches which can be actuated by permanent magnets. A disadvantage with these known arrangements is that a relatively stable frame comprising two pivot arms and a transverse yoke member must always be provided, with the frame being supported at both sides in a respective carriage for pivotal movement about a horizontal axis. The frame must be of a stable construction because it must carry the weight of the horizontal washing brush and also carry the forces acting thereon.
The invention is based on the problem of providing apparatus for controlling the movements of a roller-like horizontal rotary washing brush in vehicle washing equipment of the above-indicated kind, wherein the means supporting the brush are of a substantially simpler construction.